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I hope John Gamblin is well. I really think he has gone
completely "potty". Usually I can only manage the first two lines of
anything he writes these days and then give up.
Anyway he actually raised or stumbled upon, a
very valid and little known point about mimicry, in his line (corrected by me):
"we should not call it mimicking when it is merely a
sound copying a call" That is absolutely true in the
sense in which mimicry is usually referred to in biology. Most bird call mimicry (lyrebirds, mockingbirds, orioles, magpies, etc.)
is not in any way the same phenomenon as the usual meaning of the word
"mimicry" and is better termed: "Vocal Appropriation", as
elucidated by Dobkin (1979).
The following extract comes from my 1994 (second) article
about Regent Honeyeater vocal mimicry:
"An analysis with a more useful bearing on mimicry was
given by Dobkin (1979) who suggested some new terms and clearly differentiated
between the common phenomenon 'vocal appropriation' (the non-deceptive copying
of sounds of other species for intraspecific communication use) and the rarest
form, true mimicry, plus two other categories, vocal imitation and vocal
convergence, which are not directly relevant here. Although Dobkin's literature
search was extensive, he did not provide an example matching his largely
theoretical exposition of 'Competitive Batesian Acoustic Mimicry', one of his
suggested types of true mimicry. Krebs (1977) discussed the possible advantage
of increase of song
repertoire to deceive others into thinking that bird
density is higher than it is. Slater (1978), Krebs (1978) and especially Rechten
(1978) extended that issue into mimicry. Rechten (1978), citing one hypothesis
that 'The imitations are directed at individuals of the copied species, serving
interspecific territorial defence'. She pointed out that 'For true mimicry, one
would predict a tendency for mimics to choose predatory, larger or competing
species as models.' Batesian mimicry requires that the mimic exist at a lower
population density than the model species as applies in this case. Unlike other
'mimics', for which it is now thought that the mimicry functions to keep the
lines of communication open, the Regent Honeyeater's behaviour fits exactly into
Dobkin's and Rechten's idea of Competitive Batesian Acoustic Mimicry."
My point at the time, being that I believed that the Regent
Honeyeater does, (and still think so).
Philip
References:
Dobkin,
D.S. (1979), 'Functional and evolutionary relationships of vocal copying
phenomena in birds', Zietschrift fur Tierpsychologie 50,
348-363.
Krebs, J.R. (1977), 'The
significance of song repertoires: the Beau Geste hypothesis' Animal
Behaviour 25, 475-478.
Rechten, C. (1978), 'Interspecific mimicry in birdsong: does
the Beau Geste hypothesis apply?', Animal Behaviour 26,
304.
Slater,
P.J.B. (1978), 'Beau Geste has problems', Animal Behaviour 26,
304.
-----Original Message-----
From:
John Gamblin <>
To:
Birding-Aus <>
Cc:
Hilary Richrod <>
Date:
Thursday, 10 January 2002 13:43
Subject: [BIRDING-AUS] Moore
Magpie Mimicry
G'day All,
I was just wondering and await enlightment from you
all ..... but I have always thought that mimicry was the act of fully
mimicking?
etc. etc.
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